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Single-particle strength toward N=32: Spectroscopy of Ca51 via the Ca50(d,p) reaction

C. Ferrera1, K. Wimmer2,3,*, D. Suzuki4,†, N. Imai5, A. Jungclaus1, T. Miyagi6, Y. Utsuno7, D. Das2,8, T. Chillery5 et al.

S. Hanai5,‡, J. W. Hwang9, N. Kitamura5, R. Kojima5, S. Michimasa5, R. Yokoyama5, Y. Anuar5, M. Armstrong10,2, S. Bae5, Y. Cho9, M. Dozono11,4, F. Endo12,4, S. Escrig1, N. Fukuda4, T. Haginouchi13, S. Hayakawa5, Y. Hijikata4, G. Ikemizu11, S. Ishio13, A. Kasagi14,15, K. Kawata5, J. Li5, S. Masuoka5, B. Moon9, K. Okawa5, S. Ota12,5, H. Qin5, T. Saito5, A. Sakaue5, H. Sakurai4, Y. Shimizu4, S. Shimoura4,5, Y. Son9, T. Sumikama4, H. Suzuki4, H. Takeda4, Y. Togano4, J. Vesic16, K. Yako5, Y. Yamamoto5, K. Yoshida4, and M. Yoshimoto4

  • *Contact author: k.wimmer@gsi.de
  • †Present address: Department of Physics and Quark Nuclear Science Institute, the University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-0033, Japan.
  • ‡Present address: Department of Physics, Institute of Science Tokyo, Tokyo 152-8550, Japan.
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Phys. Rev. C 113, 044311 – Published 14 April, 2026

DOI: https://doi.org/10.1103/3fdc-j3bf

Abstract

States in the neutron-rich isotope Ca51 were populated via the Ca50(d,p) transfer reaction in inverse kinematics at a beam energy of about 14AMeV. The experiment was performed using a decelerated radioactive Ca50 beam from the OEDO facility and the TiNA2 silicon array in combination with the SHARAQ magnetic spectrometer at RIBF/RIKEN. The energies of excited states in Ca51 were reconstructed via missing mass spectroscopy, and angular distributions of protons were measured to extract differential cross sections. From a comparison with adiabatic distorted wave approximation calculations, spectroscopic factors were deduced for several states, including the ground state and excited states up to 4.2 MeV. These results are compared with shell-model calculations, as well as ab initio valence-space in-medium similarity renormalization group predictions. The data support the assignment of the 1/2− and 5/2− single-particle states and provide evidence for a candidate 9/2+ state with a structure consistent with neutron excitation into the 0g9/2 orbital. These findings contribute new constraints on the single-particle structure and shell evolution in neutron-rich calcium isotopes.

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Corrections

28 April, 2026

Correction: Typographical errors in the value for the beam energy in the first and eighth sentences of Sec. II A and in the penultimate sentence of Sec. II C have been fixed. Typographical errors in the values for target thickness in Sec. II A have been fixed.

Article Text

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Phys. Rev. C 113, 044311– Published 14 April, 2026
  • Received 2 November 2025
  • Accepted 12 March 2026
  • Corrected 28 April 2026
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